Electric storage battery.



PATENTED MAY 3, 1904.

No.v 759,066.

A. Gr. BETTS.

ELECTRIC STORAGE BATTERY.

APPLIOATION ILBD AUG. 17. 1903.

2 SHEETS-SHEET 1.

N0 MDDEL.

. Mmmm@ IEE-QE! WITNEEEEE.

PATENTED MAY 3, 1904.

A. G. BETTS. ELECTRIC STORAGE BATTERY.

APPLIATION FILED AUG.17, 1903.

2 SHEETS-SHEET 2.

:No 1:01am..

UNITED STATES latented May 3, 1904.

ANSON GARDNER BET'IS, OF TROY, NEW YORK.

ELECTRIC STORAGE BATTERY.

SPECIFICATION forming part of Letters Patent No. 759,066, dated May 3,1904.

Application led August 17, 1903. Serial No.1l69,7l8. (No model.)

To all whom it may concern:

Be it known that I, ANsoN GARDNER Bnrrs, a citizen of the United States,residing' at Troy, county of Rensselaer, and State of New York, haveinvented certain new and useful Improvements in Electric StorageBatteries, of which the following is a specification.

The invention relates to such improvements; and it consists of the novelconstruction and combination of parts hereinafter described andsubsequently claimed.

Reference may be had to the accompanying' drawings, and the referencecharacters marked thereon, which form a part of this specilication.

Similar characters refer to similar parts in the several figures.

Figure l of the drawings is a View in vertical cross-section of myimproved storage battery in its preferred form. Fig. 2 is a similar viewtaken on a plane at right angles to the plane of Fig. l, certain of theelectrodes and insulating-mats being broken away in part. Fig. 3 is aside view of one of the electrode elements. Fig. l is a similar view ofone of the insulating-mats. Fig. 5 is a vertical cross-section of amodiiied form of battery-cell. Fig. 6 is a vertical cross-section ofanother form of battery-cell.

Certain objects of my invention are to store electrical energy in anapparatus that admits of more varied conditions of use than is desirablewith the types of storage battery in general use and to secure greatereconomy in the construction and use of such an apparatus.

Other objects of my invention will appear in connection with thefollowing' description.

In the preferred form of my improved storage battery I employ solidgraphite electrodes in contact with an electrolyte comprising a solutionof a lead salt of a non-oxidizing and non-oxidizable acid with orwithout the corresponding salt of another metal more readilyelectrolytically deposited than lead, such as a strong solution of leadfluosilicate containing some free acid or a somewhat-acid solution of`l'luosilicates of lead and another metal, as copper, capable of beingdeposited by electrolysis practically free from lead from such solution.I have found by experiment and use of such a storage battery that onpassing' an electric current of moderate strength through such anelectrolyte with such electrodes peroxid of lead is deposited on oneelectrode in a dense adherent and well-conductant form, while metalliclead or said other metal is deposited on the other electrode, freeliuosilicic acid remaining in solution. Vhen the electrodes of thecharged battery are connected. in circuit to generate electrical energy,the lead or said other metal and lead pcroxid are restored to theiroriginal condition by combination with the free iiuosilicic acid intheselution, restoring the battery to substantially its originalcondition. For convenience in referring to the separate electrodes Iterm the electrode upon which peroxid is deposited the positiveelectrode and the other the negative electrode. I also refer to eachelectrode as a single-pole element for convenience in describing theapparatus, but wish it to be understood that in my improved battery anydesired number of positive-pole elements and any desired number ofnegative-pole elements may be employed in accordance with the capacitydesired for the cell. For charging the cell a rate of from ten to twentyampers per square foot of negative-electrode surface is suitable, thepotential required being about two volts. The discharge may be conductedat a very high rate without injury to the cell.

A concentrated aqueous solution of lead liuosilicate at the ordinarysummer temperature contains per liter about nine hundred grams of leadcombined with six hundred and thirty-:live grams of [iuosilicic acidwith a specific gravity of about 2.38. By the use of this solution, ofwhich about twenty pounds` represents a storage capacity of oneelectrical horse-power hour, and a suitable construction of electrodesand cellv I am able to produce a battery of high storage capacity perunit of weight. I/Vhen the electrolyte comprises a solution of leadiiuosilicate peroxid of lead is deposited on the positive electrode andmetallic lead upon the negative electrode by electrolysis during thecharging operation. W hen the electrolyte comprises a solution ofiiuosilicates of lead and copper in chemically- IOO equivalentquantities, peroXid of lead is deposited on the positive electrode andmetallic copper on the negative electrode during the charging operation.Copper fluosilicate has the necessary solubility for use in anelectrolyte for this purpose. The greater tendency of copper to depositin solid form is an advantage of its use. The lead peroxid on thepositive electrode during the period of discharge shows a tendency tobecome soft and assume a brown color instead of its original brilliantblack, and at the end of the discharge some of this material may not beso firmly attached to the electrode as to be in good electricalconnection therewith. If under such circumstances the battery besubjected to a charging-current in the opposite direction from that lastemployed, the complete removal of any loosely-attached pieces of peroxidmay be obtained with a resultant better adherence of the depositsubsequently formed. By employing electrodes both of which areinsoluble, as electrodes of graphite, I am able to thus charge thebattery at certain times in one direction and at other times in theopposite direction.

I prefer to use an exciting solution which has been very carefully freedfrom foreign metals that can deposit with the lead or other metal to bedeposited on the negative electrode in order to insure well-adherentdeposits of both peroxid and metal. The desired degree of purity can beobtained by depositing from the solution a large amount of lead or othermetal to be deposited on the negative electrode, using a soluble anodeof Vlead or said other metal, whereby the deposited metal graduallycarries out with it the metallic impurities. rIhe desired result canalso be secured with less ease by crystallization of lead fluosilicate.More or less circulation of the solution is caused by the difference indensityof the electrolyte from the different electrodes during theaction of the battery. The circulation of the electrolyte can beincreased, if desired, by any of the known mechanical means or by theintroduction from time to time of bubbles of air into the solution atthe bottom of the cell.

In operating my storage battery a small amount of gas is given on fromthe positive electrode, especially during the first few minutes ofcharging, until the graphite has been evenly coated with peroxid oflead. The result is that after the battery is completely discharged asmall amount of metal still remains undissolved on the negativeelectrode. The amount is very small, but it gradually accumulates untilwith a very large number of operations the amount of lead or other metalpermanently removed from the solution is considerable. The introductionof air for circulation purposes corrects this by dissolving smallamounts of metal from the wellknown reaction between dissolved oxygen,

metallic deposit.

tisanes metal, and an acid forming a soluble salt with the metal.

I have'found in working a storage battery constructed as above describedthat a small quantity of lead peroXid separates from the positiveelectrode particularly during discharge and that the same phenomenon mayoccur with the metallic deposit.

Features of this invention consist in providing the electrodes withsurfaces from which the separation of the electrodeposit takes placeless easily and in providing means whereby any of the electrodepositwhich becomes thus separated from an electrode is caught and maintainedin circuit during the discharge of the battery, such deposits being thusdissolved and restored to their original condition in solution, therebyretaining the strength of the electrolyte. For this purpose it is onlynecessary that the deposit so separated from theelectrodes should bemaintained in electrical connection with either a positive or a negativepole element of the battery. In order to secure the fulleciency of thedischarge, the peroXid thus separated from its electrode should beretained in contact with a positive-pole element and themetallic depositso separated in contact with a negative-pole element. However, bycollecting separated peroXid on a negative-pole element or separatedmetallic deposit on a positive-pole element a resolution of suchdeposits will be accomplished. Any known means may be employed for thuscatching and maintaining in circuit during the discharge of the batterydeposits separated from the electrodes, adapted, preferably,to maintainthe separated lead peroxid in contact with a positive-pole element andthe separated metal in contact with a negative-pole element of thebattery.

For certain purposes of this invention a solution of metallic salts ofvarious non-oxidizing and non-oxidizable acids may be employed,including fluorine acids-such as fluoboric acid, iiuotitanic acid,luosilicic acid, and others-and for certain purposes of the inventionelectrodes of material other than graphite may be employed-such ascarbon, platinum, or other insoluble materialfor one or both electrodesor the combination of an insoluble positive electrode with a negativeVelectrode of copper, silver, or other metal of less electromotive forceof solution than the I prefer, however, to use solid graphite, and moreparticularly artificial graphite, for the electrodes, for the reasonthat their use insures a more firm adherence of the electrodeposit thanthe other substances named.

By the terms non-oxidizable and nonoxidizing acid I mean acids which arenot oxidized or reduced by conditions obtained in working the battery.

Referring to the figures of the drawings, l

IOO

IIO

ISO

lrepresents the body of the cell, which may be Aformed et wood, providedwith a rubber lining 2, within which are contained the elec-V trolyte 3and a plurality of positive-electrode elements 4, arranged inalternation witha plurality of negative-electrode elements 5, adapted tobe connected in circuit by means of the wires 6 in the usual manner. Theelectrolyte is prepared as above described. Each of the electrodeelements comprises a grating of artiiicial graphite with numerousopenings 7 therein permitting free circulation oi the electrolyte.Plates or mats 8 of insulating material, such as rubber, are supportedon opposite sides or' each electrode element, so as to cover thevertical side surfaces o1 the gratings and prevent the formation ofelectrodeposit thereupon. These mats are provided with apertures 9,corresponding in location with but of smaller area than the respectiveapertures in the electrodes interposed between said mats. The aperturesin the mats permit the circulation therethrough ot the electrolyte; butthe bodies of the mats where projecting upwardly above the bottom wallof the several apertures in the electrodes serve to form in the bottomof each electrode-aperture a pocket 10, adapted to catch 'fallingdetached electrodeposit and retain the same in contact with the body ofthe electrode. The insulating-mats also cover the side surfaces of theelectrode at the corners bordering the apertures therein, thuspreventing the formation on such corners of a growth of electrodeposit,which mig'ht tend to short-circuit the battery.

In Fig. 5 I have shown a copper tank 12, which forms the negativeelectrode, within which are contained the electrolyte 13 and thepositive electrode 14 in the form of a perforated plate of graphite.Blocks of graphite 15 may be interposed at intervals between saidgraphite plate and the side walls of the copper tank from which they areinsulated by rubber blocks 16, said graphite blocks forming inconnection with the graphite plate pockets 17, adapted to catch thefalling detached electrodeposit and retain the same in contact orelectrical connection with the positive-pole element.

In Fig. 6, 18 represents the body ot' the cell; 19, the positiveelectrode; 20, the negative electrodes, and 29 the electrolyte. Theseelectrodes are perforated plates of graphite formed with ribs or lianges21, extending' horizontally along their sides, adapted to receiveloosened electrodeposit and retain the same in contact with theelectrode. The electrodes are adapted to be connected in circuit by therespective wires 22 and 23. Beneath the electrodes is placed a graphiteplate 24, adapted to receive any loosened electrodeposit which fails tobe caught by the flanges 21,which plate is in electrical connectionthrough the rod 25 with the contact-piece 26, adapted to be engaged. atcertain times by one end of the contact-lever 27, the opposite end ofwhich constitutes an armature for the electromagnet 28 in circuit withthe wire 22. The construction is such that when the battery is subjectedto a chargingcurrent the armature end 30 of the contact-lever 27 .isreleased or repelled by the magnet, causing separation of said leverfrom the contact 26, and thereby cutting the plate 24 out of circuitduring the charging of the battery. When the battery is employed as agenerator, the magnet 28 is energized to attract the armature end 30 ofthe contact-lever, causing the same to engage the contact 26, therebyconnecting in circuit the graphite plate 24 through the lever 27 andwire 31, which connect said lever with the wire 22. In the constructionshown in Figs. 1, 2, and 3 the side surfaces of the electrodes may beformed with vertical grooves 31, adapted to permit the free dischargeupwardly through the cell of bubbles of gas.

As a means for introducing air into the electrolyte for the purposeabove stated I have shown in Figs. 1 and 2 a series of airsupply nozzles35, projecting into the bottom portion ot' the cell, which nozzles arecon nected exteriorly or' the cell with a common air-supply pipe 36,communicating' with a source of air-supply, such as an air-pump. (Notshown.)

In the construction shown in Figs. 1, 2, 3, and 4 the apertures in theelectrodes may bc formed to extend entirely through or only partlythrough the electrodes, both forms being shown in Fig'. 2.

I make no claim in this application to the method of accumulating' andusing electrical energy disclosed herein, as the same forms thesubject-matter of a separate application filed herewith.

IOO

WV hat I claim as new, and desire to secure by Letters Patent, isv

1. In an electric storage battery, the combi-` nation with suitableelectrodes, or' a solution or' a lead salt of a non-oxidizing andnon-oxidizable acid, which forms a readily-soluble salt with lead.

2. In an electric storage battery, the combination with suitableelectrodes, of a solution or a readily-soluble lead salt ot' a iuorinacid.

In an electric storage battery, the combination with suitableelectrodes, of a solution et lead iiuosilicate.

4. In an electric storage battery, the combination with suitableelectrodes one of which is insoluble, of a solution of a lead salt of anonoxidizin g and nonoxidizable acid, which forms a readily-soluble saltwith lead'.

5. In an electric storage battery, the combination with suitableelectrodes one of which is insoluble, of a solution or' a lead salt of afluorin acid.

IIO

6. In an electric storage battery, the combination with suitableelectrodes one of which is insoluble, of a solution of leadfluosilicate.

7. In an electric storage battery, the combination with electrodes, oneof which is of graphite; of an aqueous solution of a readilysoluble leadsalt of a non-oxidizing and nonoxidizable acid.

8. In an electric storage battery, the combination with electrodes, oneof which is of graphite, of a solution of a lead salt of a iluorin acid.

9. In an electric storage battery, the combination With electrodes, oneof Which is of graphite, of a solution of lead uosilicate.

l0. In an electric storage battery, the combination With insolubleelectrodes, of a solution of a lead salt of a non-oxidizing andnonoXidiZable acid which forms a readily-soluble salt With lead.

11. In an electric storage battery, the combination with insolubleelectrodes, of a solution of a lead salt of a iuorin acid.

12. In an electric storage battery, the combination with insolubleelectrodes, of a solution of lead uosilicate.

18. In an electric storage battery, the combination with electrodes ofgraphite; of an aqueous solution of a readily-soluble lead salt of anon-oxidizing and nonsoxidizable acid.

14. In an electric storage battery, the combination with electrodes ofgraphite; of asolution of lead salt of a iuorin acid.

15. In an electric storage battery, the combination with electrodes ofgraphite, of a solution of lead iiuosilicate.

16. In an electric storage battery, the combination with suitableelectrodes, of a solution of readily-soluble salts of lead, and anothermetal capable of being electrodeposited practically free from lead fromsaid solution.

17. In an electric storage battery, the combination with suitableelectrodes, of a solution of iuorin acid salts of lead, and anothermetal capable oi' being electrodeposited practically free from lead fromsaid solution.

18. In an electric storage battery, the combination With suitableelectrodes; of a solution of fluosilicates of lead, and another metalcapable of being electrodeposited from said solution practically freefrom lead.

19. In an electric storage battery, the combination with suitableelectrodes; of a solution of readily-soluble lead and copper salts ot anon-oxidizing and non-oxidizable acid.

20. In an electric storage battery, the combination with suitableelectrodes; of a solution of lead and copper salts of a iuorin acid.

21. In an electric storage battery, the combination with suitableelectrodes; of a solution of lead and copper iiuosilicates.

22. In an electric storage battery, the combination with electrodes ofgraphite; of a solution of readily-soluble lead and copper salts of anon-oxidizing and non-oxidizable acid.

23. In an electric storage battery, the combination with electrodes ofgraphite; of a s0- lution of lead and copper salts of afluorin acid.

24. In an electric storage battery, the combination Withelectrodes ofgraphite; of a solution of lead and copper iiuosilicates.

25. In an electric storage battery, having, in combination With suitableelectrodes, an electrolyte from Which active materials are depositedupon the respective electrodes on charging, and which redissolves saidactive materials on discharging, a conductive receptacle disposed tocatch falling detached active material in combination with means wherebysaid receptacle is maintained in circuit during the discharge of thebattery.

26. In an electric storage battery, having, in combination with suitableelectrodes, an electrolyte from Which on charging are deposited upon therespective electrodes lead peroxid andl lead, or equivalent metal, bothof which active materials are redissolved on discharge; a conductivereceptacle disposed to catch falling detached active material, incombination with means whereby said receptacle is maintained in circuitduring the discharge of the battery.

27. In an electric storage battery, having, in combination with suitableelectrodes, an electrolyte from-Which active materials are depositedupon the respective electrodes on charging, and which redissolves saidactive materials on discharging, an electrode of solid graphite havingnumerous small surfaces arranged at `angles one to another.

28. In an electric storage battery, having, in combination With suitableelectrodes, an electrolyte from which activeimaterials are depositedupon the respective electrodes on charging, and which redissolves saidactive materials on discharging, an insoluble electrode provided Withlaterally-extending surfaces disposed to catch and hold in electricalconnection with the electrode detached falling active material.

29. In an electric storage battery, having in combination with suitableelectrodes, an electrolyte from which active materials are depositedupon the respective electrodes on charging, and which redissolves saidactive materials on discharging; an insoluble electrode formed With sideapertures in combination with insulating material applied to the sidesurface of said electrode covering said side surface at the corner edgesbordering said apertures.

IOO

IOS

IIO

having laterally-cxteuded surfaces adapted to catch and hold inelectrical connection With said electrode detached active material.

31. In an electric storage battery, having, in combination With suitableelectrodes, an electrolyte from which active materials are depositedupon the respective electrodes on charging, and which redissolves saidactive materials on discharging, an insoluble electrode provided withapertures in its opposite sides, in combination with apertured plates ofinsulatingmaterial located on opposite sides thereof; the apertures insaid insulating-plates corresponding in location with and being of lessarea respectively than those in the interposed electrode.

3Q. ln an electric storage battery, the combination with an electrolytecontaining in solution a lead salt of a non-oxidizing and nonoxidizableacid which forms a readily-soluble salt with lead; of electrodes incontact with said electrolyte, one of said electrodes cour prising anapertured plate of insoluble con ductive material; and plates ofinsulating material located on opposite sides of said electrode providedwith apertures respectively corresponding in location with, but smallerthan those in the interposed electrode, Whereby the edges of theelectrode bordering the apertures therein are covered and protected froman excess of clectrodeposit by the insulating-plates, and pockets areformed in the bottoms of the respective apertures in the electrodebetween neighboring insulating-plates adapted to receive and retaindetached electrodeposit formed during the operation oiI thc battery.

33. 1n an electric storage battery, the combination with suitableelectrodes, and an electrolyte from which active materials are depositedupon the respective electrodes on charging, and which redissolves saidactive materials on discharging; of means for introducing air into theelectrolyte near the bottom of the cell. p

34. In an electric storage battery, the conibination with insolubleelectrodes; andan electrolyte comprising a solution of a lead salt of anon-oxidizing and non-oxidizable acid which forms a readily-soluble saltwith lead; of means for introducing air into the electrolyte near thebottom oi the cell.

In testimony whereof I have hereunto set my hand this th day of August,1903.

ANSON GARDNER BETTS.

Witnesses:

FRANK C. CURTIS, E. M. OREILLY.

